How are your LOs doing with this skill?
I put Hannah's shape sorter in front of her and she can lean on that and hold herself up right for a little bit of time. I usually just need to prop her against something and she'll stay up on her own. Today I had my feet in a V form and she was sitting up against though. I removed my feet and she was able to balance herself for quite a bit. When she started to fall forward, she put out her hand to steady herself. I think if she just gets a little more arm strength, she'll be tripodding in the very near future.
Re: Sitting up
LO is doing the same. I use my boppy to prop her but she lean forward. Sometimes she can hold for a bit.
DD seems to be forgoing the tripod and going from leaning really far forward to sitting straight up.
It's funny because she obviously can do it (and has once even sat by herself for about a minute), but she's a very cautious baby and if she isn't touching me in any way she starts to fall over. I put her in the V between my legs too, and she sits just fine without putting any of her weight on me for a long time. Still, as soon as I'm not touching her anymore, she tumbles!