"Math involves an ascending progression of concepts. Slow starters in math are unlikely to catch up."
ChildUp Early Learning Key #4: The goal is to be quite school-ready
Math and language are essential for the proper development of a Child’s intellectual and social skills, which is why it’s so important to pay attention to them from day one. Well-prepared (advanced) Children starting kindergarten and elementary/primary school with solid foundations in math and language will keep this precious advantage for life.