The 19 month old development checklist is important because it helps parents and caregivers track the progress of their child’s development and identify any potential delays. The checklist includes a variety of skills that a child should be able to do at 19 months, such as speaking in full sentences, stacking blocks, and scribbling with a crayon. If a child is not able to do any of these things, it may be an indication that they need some extra help and support.