My family portrait only shows one baby when my vampire couple had twins.

[ShadySimmer61]

I put out one antique spellcaster bassinet because I didn't know they were having twins or that the baby would come in a special vampire bassinet, which the second baby appeared in. I read about problems with only one baby showing up in the family portrait so I moved them to a new lot and then moved them back and now they are both in special vampire bassinets, but the family portrait is still only showing one baby. 

[ShadySimmer61]

Well once I raised them to toddlers they are both now showing up in family portrait.