16mo not walking, getting concerned…

I know it’s technically not concerning until 18 months but I can’t help but worry. She walks when shes holding my hand or walks pretty fast with her walker but just will not take steps on her own.

Her pediatrician will not refer me to a specialist until 18 months but I was wondering who I should see to just get a check up. It wouldn’t hurt to see a physiotherapist maybe? She was also a late crawler (11.5months) if that changes anything.

Im due in a couple of months with her brother and would LOVE for her to be walking by then. She will be exactly 18 months on my due date so would love to get the ball rolling before baby arrives.

Any experiences with a late walkers?