18" Boy's and 22" Girl's Bikes?

My kids have been riding since age 3, and two of them are now in the
awkward point of not fitting any of the "standard" sizes. Does anyone
know of a good quality multi-speed 18" (tire, not frame) boy's bike?
Though not quite as critical, I also am looking for a girl's 22" in at
least a six-speed. TIA for any help you may provide! pcc