[GRO] Infant don't act on their achieved milestones when invited over/visiting

I can confirm this is an issue for me as well. Infants are completely helpless when they are npcs and don't act on their achieved milestones (but they also don't achieve them at the stay over either, it tries, but never happens) - Mine I noticed at stay overs. They otherwise do have their milestones when playing in their household.