The text messages from your wife can be introduced at the hearing as evidence against you but I doubt they will be the sole factor considered by the judge in making a custody determination. Your wife should testify at the hearing explaining the circumstances and admitting that she acted inappropriately and explaining how she would handle it if the situation arose again. Unless your wife is physically assaulting the children then I would not anticipate an order prohibiting the children from being with her. The judge is supposed to weight the custody factors as set forth in the Custody Act:
23 Pa.C.S.A. § 5328
Purdon's Pennsylvania Statutes and Consolidated Statutes
Title 23 Pa.C.S.A. Domestic Relations
Part VI. Children and Minors
Chapter 53. Child Custody
§ 5328. Factors to consider when awarding custody
(a) Factors.--In ordering any form of custody, the court shall determine the best interest of the child by considering all relevant factors, giving weighted consideration to those factors which affect the safety of the child, including the following:
(1) Which party is more likely to encourage and permit frequent and continuing contact between the child and another party.
(2) The present and past abuse committed by a party or member of the party's household, whether there is a continued risk of harm to the child or an abused party and which party can better provide adequate physical safeguards and supervision of the child.
(3) The parental duties performed by each party on behalf of the child.
(4) The need for stability and continuity in the child's education, family life and community life.
(5) The availability of extended family.
(6) The child's sibling relationships.
(7) The well-reasoned preference of the child, based on the child's maturity and judgment.
(8) The attempts of a parent to turn the child against the other parent, except in cases of domestic violence where reasonable safety measures are necessary to protect the child from harm.
(9) Which party is more likely to maintain a loving, stable, consistent and nurturing relationship with the child adequate for the child's emotional needs.
(10) Which party is more likely to attend to the daily physical, emotional, developmental, educational and special needs of the child.
(11) The proximity of the residences of the parties.
(12) Each party's availability to care for the child or ability to make appropriate child-care arrangements.
(13) The level of conflict between the parties and the willingness and ability of the parties to cooperate with one another. A party's effort to protect a child from abuse by another party is not evidence of unwillingness or inability to cooperate with that party.
(14) The history of drug or alcohol abuse of a party or member of a party's household.
(15) The mental and physical condition of a party or member of a party's household.
(16) Any other relevant factor.
(b) Gender neutral.--In making a determination under subsection (a), no party shall receive preference based upon gender in any award granted under this chapter.
The above answer is intended solely for general informational purposes and does not create an attorney client relationship. You should consult with an experienced attorney regarding all of the details of your particular situation before taking action.
You need to specify whether you have an attorney. If you have an attorney, you should ask him/her this question. Clearly, your Wife should not make these types of comments to the children regardless of whether this is her opinion. I am assuming that the mother will show this message to the Judge and he/she will not be very happy that this occured. Most court orders prohibit either parent or third parties from making derogatory statements about the other parent in the presence of the children, so you should instruct your wife never to do it again. While it may not ultimately harm your chances of being awarded primary physical custody of the children, this type of behavior is very damaging to the children. I would not expect the court to prohibit the children from having contact with your wife, but a reprimand is likely and if it happens again, drastic measures may be taken.
My response is based solely on the limited information contained in the question. It is not meant to substitute your attorney's advice.