When is it okay to give a child ice cream?

My fiancé & I live 1,200 miles away from our families. His parents & his brothers (one brother is taking leave from the Air Force to come down) are coming down for my fiancé’s birthday in July to come meet their granddaughter for the first time as well. This is his first birthday as a dad. She’ll be 1 day shy of turning 6 months exactly by then. Would it be okay to give her a tiny bite of ice cream at his birthday celebration when they visit? I’m not talking a whole bowl or anything but just a baby spoon full. Just trying to plan ahead.