I don't shoot a ton of family photography, but when I do in-home sessions are definitely the way to go. In Chelsey and Ryan's case, their son was still napping when I got there so we were able to sneak in a quick couple's session (plus fur babies) before he woke up.
If you have older kids then planning an activity the whole family can get into, such as baking cookies, making dinner, playing outside or building a fort also makes for some lovely, candid family photos. Kids (and adults) are generally most comfortable in their own environment and being home helps us truly capture the everyday moments.
Being home also takes the pressure off trying to get everyone dressed up and staying "nice." If you all want to play in the mud together, play in the mud. If you want to walk down the creek or stroll around your neighborhood, let's do it. If the baby is still sleeping for the first half of the shoot, let him sleep.
Kids don't often want to cooperate when they aren't comfortable. If the session is less about making them pose and more about capturing who they are and how they interact with you, the genuine smiles tend to come out, it's less stressful for everyone and the result can be truly lovely.