Seeing as how Hearthfire revolves around building a household. Are you going to be able to do any of the following...?
This is edited as after reading some replies and doing some research much of my Fable-type suggestions are anti-lore or just plain infeasible due to the time-scale of Skyrim.
Nevertheless here are my suggestions:

• Rename your orphan.
  
• Teach them and train them in the ways of combat, magic or sneak etc - I.e. practice with your son/daughter with wooden swords/axes/warhammers/etc in the yard or something.
  
• Send them out begging/stealing for the Dark Brotherhood/Thieves Guild, Squiring for the Companions/Stormcloaks/Legion or studying at the Bards/Winterhold College.
  
• Turn them into a werewolf/vampire.
  
• More child clothing. Little kids would want to dress like their Dovaahkin Dad/Mom.
  
• Child-sized wooden swords and toys, etc. The children of Skyrim seem to do nothing but play tag and get bullied by Braith.
  
• More Children of other Races around; Argonion, Khajiit, etc.
  
• More child-occupations; such as child thieves, child smithies, etc.

The whole point of Skyrim is adventuring, I don't want it to be like the Sims at all - although I did enjoy the Fable system of families, it was lots of fun to eat blueberry pie infront of your starving family as the bad guy! >

What are your thoughts guys?

No.
Not sure.
No.
No.
No.
Kids can't die
No.

That's a shame, they should definitely add all that stuff in - it would be awesome. (And I meant a funeral for your kids when they die after growing up, not when they are children)

no to all,sounds like the sims in furs.
unless you could also;

1.adopt children then sell them as slaves.

2.throw recalcitrant children into you fully accoutered home skeever pit and charge the locals money to watch.

3.train them as assassins or thieves and then sell them to the respective guilds.

4. have them stuffed and mounted when they die.

cheers

They shouldn't really. Ageing kids is slightly unpheasable for a game like Skyrim that is in real time. There aren't cut scenes and the possibility to magically skip forward months and years.

I can see trianing them with wooden wepons in the yard fun, but i agree with your point, its real-time, you would die before them, and that means the game would end you would have to start agian, I like Skyrim cos it's Skyrim....and sims cos it's sims....

According to Lore, you are the absolute Last Dragonborn.

There will be no Dovahkiin Legacy.

Until Bethesda says otherwise.

"Dovahkiin Legacy"

You're adopting a child, they haven't got your blood, therefore they won't be Dovahkiin.

This.

I have almost 300 hours on my last playthrough and the days passed was just over two years, so the whole idea of aging just wouldnt be feasable unless they severly speed up the gameplay clock which would then make it illogiclal, i.e. three days would pass to walk from riverwood to whiterun while it only took a minute of real time.

Maybe they should add adoptable young advlts then, so that we can do things which would be logical, for example, training them with swords and turning them into a vampire or whatever.

...I think after a certain age, orphanages just turn you loose.

Well, you've seen the kids who just wander the streets in Whiterun for example. There could be a kid who says;

"I was kicked out of the orphanage. I have nowhere to go. I tried to join the Companions but... my sword-arm isn't good enough."

Then you can reply;

"Oh, you could come and live with me. Maybe we could train that sword-arm?"

Etc etc.

I hoped that the DLC would

• Add more Spouses/children + of other races
  
• Add more interactions with NPC's you've married
  
• Fix/Add to marriage, Options, different locations Solitude even?

Edited my thoughts into the original post; refer to that into replies.
After reading some of these responses and doing some research and, believe it or not, some actual thinking.
I realise a few of my suggestion were simply not possible in a game like Skyrim.
However I still think some of them have merit and would add to immersion.
As stated; refer to the original post now.

Please keep the feedback coming, and if you agree show support. If you disagree, say why!

Also the marriage system does need to be expanded and there do need to be children of other races for sure (some Argonian Eggs! )

No.
I Wish.
No.
No.
Little Clothing Changes.
Yes, kids have wooden swords

I think it's a great idea, it would be cool to go hunting with them and stuff. Or maybe be able to adopt teenagers (like 15/16 year olds) to train them and stuff, have like a family skill tree or something But i don't think ageing would be that good of an idea as you'll get older yourself etc. But good ideas!

My Vampire Lord, Nocturne, disagrees with your assessment of aging.

In all honesty, I just wish I could train my young adopted son, a fellow Breton named Francois, a good kid from the Honorhall Orphanage, in the incredible arts of magic and even teach him the finer things - like necromancy. Every child should learn how to raise the dead!

...That, and I'd like for him to have his last name match his "pa's" last name.

For the romance part of your title, none to be found. You have almost no dialog with your wife/husband in skyrim. I walk in and tell her to give me my share of the profits from the store and make me something to eat. That is really all the dialog to have with your wife/husband.

Keep the ideas coming; in essence I just want the kids of Skyrim and the 'family' idea to be a bit more immersive; even if there is no aging and it is limited.

1. No. They're 9-year-olds, not babies. If you don't like the name, don't adopt the kid.
2. Why not? It could be a game. Teach them fighting, magic, or stealth.
3. They don't age. But dependant on what you teach, they could plan to join the Companions, the Mages College, or the Thieves Guild.
4. That's just SICK!!!
5. OK, more clothes options is good. And fix the 'streaking' glitch.
6. Already done, I think.

I adopted two girls. I returned home one day to find them arguing. It was great to be able to step in and have dialog options like "Both of you knock it off." or sending one or the other to their room. One girl came home with a little fox following her and asked if she could keep it. Those two things weren't really on topic, but I just thought these were two really neat interactions.

On topic: I was surprised to find out that I could give them gifts...and even more surprised when the only thing I could give her out of my entire (and considerable) inventory was one of two daggers. So I gave her an elven dagger with a soul capture enchant. She excitedly thanked me then ran over to the fighting dummy in her room, that I some how never noticed before, and started hitting it. Later I found a wooden sword and gave that to my other daughter who did the same thing. Now I see them walking around town with a dagger or wooden sword on their hips. It's pretty great.

So based on this I'm hoping that maybe they'll eventually allow us to either send them out on tasks or accompany us on adventures. Either one would be awesome. I'd also like to create two more Babettes. >)

Yeh I just want them to add more wooden swords for kids, some child-sized bows/arrows/crossbows/bolts, etc - the ability to train them in some basic magic and in doing all this prepare them to join a guild of your choosing (companions, winterhold, dark brotherhood, etc.)

Also they should add some more children to the world, especially of other races like Kahjiit and Argonian - it would be great to see maybe one or two child thieves in each city that run around and steal bread from stalls and escape the guards by hiding in small places etc.