Hi. Silly question but it's been on my mind for days now!

I'm getting to the end of my first couple of weeks with my first 2 mindees. I've been considering their starting points and noting things down rather than doing observations yet.

For some reason this one stumps me:
Maths - Numbers - Birth to 11m: Notices changes in number of objects/images or sounds in group of up to 3.

I cannot think of a way to determine this in a baby of almost 1 year old. How can I incorporate this into an activity to check the child's progress?

Very grateful for any links or ideas please. I'm sure it'll be something I am overthinking but I'd rather check. Thanks so much.

Helen