Sizing hand knitted clothes

[AnneShirley18]

Hi, I have a prolific knitter as a mother-in-law. She is so talented! She makes stunning clothes but she used to make me approximately 2 cardigans a week. This was so generous but I actually couldn't keep up and baby rarely wore same thing twice and lots haven't been worn at all!
I did have a gentle chat a couple of years ago as I was so overwhelmed with stuff and she now makes 3 for each season. The kids have tripled and I have a loft full of barely worn/unworn hand knits. I used to give lots away to coworkers and friends but noone's had a baby in ages! I'm going to take them to a carboot but I'm stumped on sizing. I've had a look on line but can't find a handy sizing chart to help me categorise each age range from 0-3 mths up to 10. Can anyone help me out?

[Skybyrd]

https://www.goodknitkisses.com/baby-sizes-chart/

Actual average baby sizes. The adjustments for 'ease' are in smaller writing at the bottom of the chart.

https://www.craftyarncouncil.com/standards/child-youth-sizes I'd use the above baby adjustments as a rough guide for ease.