Assuring can be used as an adjective, too: you are an assuring parent if you exhibit confidence in your child's abilities, which will bolster his self confidence.

What type of word is assuring?

verb (used with object), as·sured, as·sur·ing. to declare earnestly to; inform or tell positively; state with confidence to: She assured us that everything would turn out all right.

Is assuring a noun?

The act of assuring; a declaration tending to inspire full confidence; that which is designed to give confidence. The state of being assured; firm persuasion; full confidence or trust; freedom from doubt; certainty.