It is very important for parents, particularly of small children, to get some child-free leisure time in every day. But you are a parent 24/7, so no time is completely child-free. Most guilds understand when you have to AFK for emergencies and you don't make a habit of it, but few guilds want you to raid with them if your AFKing is more regular. Also, start times for parent-friendly guilds are post-bedtime which is often a couple hours later than guilds with child-free players who eat dinner at their desks while preparing for their raids.
Are there many family friendly guilds out there, conducting raids around bedtime schedules and late night feedings? Two "advertised" in the comments and I know that Guildwatch sometimes mentions them in the recruiting section, but not very often. With realm and faction transfers easily attainable these days, transferring to a server with a guild more suited to parental priorities may be the right thing for many players -- if they know how to find them.
Are you in a raiding guild that is parent friendly? If so, what realm and faction and are you recruiting? Let's turn this Breakfast Topic into a listing for parent-friendly raiding guilds.