You can teach him/her the simple maths now and hire a tutor later when it starts to be complex or difficult for you.
Don't deny him/her the opportunity 

My son likes LR more this days because I put him on a rotating chair (office chair: I hold him all the time to avoid falling) and rotate it slowly during multi-sensory (after every word/picture)

Thank you so much for your response. Much appreciated.

Hi

I have a 7 months old baby, which I have started teaching him flash cards when he was 4 months. Nowadays he is no longer looking at the flash cards, but my mouth. Is he learning or should I do something for him to focus on the flash cards? He sometimes laugh at me when I call out the words