Growing together is not really a pack that has much cross-compatibility. Let me be honest about the downside when playing families: You don´t have pre-school. As far as infants they are SUPER annoying but super lovely also. You die of baby fever as well as find them extremely annoying. You barely don´t have time to get the milestones. But otherwise the family dynamics can be changed super easily. In game, you get pop-ups often about family dynamic to change and whatnot. You can also change on cas.
Probably the most annoying is midlife crisis. I am not sure if it´s growing together or parenthood since I got them both at the same time. So do your research.
But overall, I feel like it´s a good pack, if you are really interested into family playing probably this is the pack. If you are interested in education of kiddos, parenthood is the pack.
Overall I have a positive review about it really.