So many parents wonder about their child's love language, and admittedly, determining the love language of a young child requires some educated guesswork. Why? Because young children can't yet verbalize their love language.
Try the following exercise:
Ask him or her to draw or call out some ways parents love their children. You should try not to guide their drawings or answers, limit their responses, or require more responses than what he or she is prepared to give at the time you ask. Depending on the child's attention span and the time of day, you may get many answers, or you may get very few. If it seems like slow going, then you may want to secretly explore the subject of love with your child for a week or so until you can deduce what he or she perceives as love.
It's never too late to start loving better. Gary Chapman has written resources to help you connect with your child and grow personally.