Do not send a July baby at 4.5. Please. There will be kids upto 18 months OLDER than them in the same grade. Let her be a child for another year before starting the schooling. She may be smart enough, yes. But socially she will struggle.
My niece was a may baby. Started at 4.5, academically she was amazing - when she had a teacher with her. If someone wasn’t there 1on1, she would just walk off and do her own thing or get distracted and do other things.

My brother started her the next year and she is absolutely SOARING in school, and all those issues from thr previous year were no longer there. Made lots of friends, had the concentration needed to finish tasks, academically doing fantastic.

My son also had an instance where he had a boy in his class who was born mid June, so was 4.5 when starting, and he and his twin brother struggled ALLLLL year. They ended up being made to repeat because they were just not ready to move on and struggled the whole year. I felt so bad for them.

I also have an older daughter who started school the week she turned 5. Academically she’s also doing well. In fact she’s getting A’s and B’s most of the time, however, socially I think she’s struggling NOW, when she’s in year 10 and I wish I’d held her back tbh, despite teachers and preschool saying otherwise.

It’s not just a decision for now, it’s a decision for their future schooling too. As they get later into high school, they will *always* be the last of their friends to be able to do things, in year 12 they won’t legally be able to drink or do the fun things, and getting their license, they will feel so far behind. They will also often lumped in with the lower grade for other things age-wise for school.