They usually are not that strict with ages. I'm pretty sure you can take a younger child as long as you leave if he/she is being too disruptive (same is true for any age, really)
Not sure where you are located but the Placentia Library has 0-2 lapsit storytime. Also there are some in Orange, Anaheim Hills and Fullerton that have the 0-2 or 0-3 storytime. HTH!
Re: Storytime
DD #2: BFP: 8-19-18 EDD: 4-30-19