She meets the definition of family in this state which would qualify this assault as a felony.
"Sec. 22.01. ASSAULT. (a) A person commits an offense if the person:
(1) intentionally, knowingly, or recklessly causes bodily injury to another, including the person's spouse;"
"(b-1) Notwithstanding Subsection (B )(2), an offense under Subsection (a)(1) is a felony of the second degree if:
(1) the offense is committed against a person whose relationship to or association with the defendant is described by Section 71.0021(B ), 71.003 (this includes baby mama), or 71.005, Family Code;"
A broken bone is generally considered serious bodily injury and would seem to qualify this incident as Aggravated Assault.
"Sec. 22.02. AGGRAVATED ASSAULT. (a) A person commits an offense if the person commits assault as defined in Sec. 22.01 and the person:
(1) causes serious bodily injury to another, including the person's spouse; or
(2) uses or exhibits a deadly weapon during the commission of the assault.
(B ) An offense under this section is a felony of the second degree, except..."
So yeah, it is a felony. Will he plead to a lesser charge? Maybe, but from the information we have now it is a felony.