Primes or zooms for children?

Prime all the way, my 85mm never leaves my camera!!

I used my 50mm 1.8 for the newborn pictures I did of my daughter and used the 50mm 2.5 compact macro since I sold the 1.8. I've recently sold the 2.5 and purchased another 1.8 and the Tamron 28-75mm 2.8 as she's a proper little runaround now at 16 months and I need the versatility the zoom gives me in range.

Ideally I'll pick up a second cheap body and put the zoom on one and keep the prime on the other. I also plan on getting the 85mm 1.8 although I hear that's better on FF rather than the crop sensors.

Unless you can afford the 24-70 primes all the way. The Canon 40mm Pancake 2.8 is a good inexpensive prime lens to get into at only $149, and it's wide enough for shooting families. I also recommend adding a flash setup to your wish list.

I like my primes, so I have the fast f/stops that my zooms can't give me. I feel a lot more involved in the shoot too with primes. I'm more up close, and interacting with the child as I shoot. Plus, you just can't beat the sharpness of a good prime!

Just a suggestion. Given the lenses you have in your sig I would sell the 70-200f4 and invest in a 70-200f2.8

My most used lenses are 70-200f2.8,50f1.4, and 24-70

24-70 is a good all rounder for children

Always like the primes better