Mum BF me for 3 months, then onto formula.
She BF my next sister for 6 months, and my youngest sister she BF for 14 months.
It didn't really influence my decision in any way.

My MIL BF DH for 12 months and then each sister for about 6 months.

I BF DS for 10&1/2 months and DD for 7 months.