I have a 20 yr. step daughter living in my home her mother left to be with someone else the girl is acting irrational what can I do to have her legaly removed clay in Tx

I would seek to get MY step daughter some help through her trauma, if indeed her mother left you both. You both could use some help, but you have no details about your history with her or whether you raised her. That being said the local laws of eviction should apply.