If the mother touches her child’s ‘awrah, does that invalidate her wudu?
Question

Does touching the ‘awrah of a six-year-old child invalidate wudu?
Praise be to Allah.The scholars (may Allah have mercy on them) differed as to whether wudu is invalidated by touching the ‘awrah of a minor.
Some of the scholars are of the view that wudu is invalidated by touching the ‘awrah of a minor, as it is invalidated by touching the ‘awrah of an adult.
Ibn Qudaamah (may Allah have mercy on him) said:
According to the report which says that wudu is invalidated by touching the private part, there is no differentiation between one’s own penis and that of another person, or between the penis of a minor or an adult.
End quote from al-Mughni (1/118)
The Standing Committee for Issuing Fatwas was asked: Does touching my child’s ‘awrah when changing his clothes invalidate my wudu?
They replied:
Touching the ‘awrah without a barrier invalidates wudu, whether the one who is touched is a minor or an adult, because it is proven that the Prophet (blessings and peace of Allah be upon him) said: “Whoever touches his private part, let him do wudu.” The private part of the one who is touched is the same as the private part of the one who touches another [with regard to the ruling].
End quote from Fataawa al-Lajnah ad-Daa’imah (5/265).
The second view is that wudu is not invalidated by touching the ‘awrah of a small child.
Ibn Qudaamah (may Allah have mercy on him) said: It was narrated from az-Zuhri and al-Awzaa‘i that no wudu is required for touching the penis of an infant, because it is permissible to touch it and look at it.
End quote from al-Mughni (1/118)
Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) was asked: Does washing the private parts of an infant invalidate wudu?
He (may Allah have mercy on him) replied:
No; that is, touching the private part of an infant does not invalidate wudu; rather touching a person who has reached the age of puberty does not invalidate wudu, unless that is done with desire. Thus we may reconcile between the hadiths of Talq ibn ‘Ali and Busrah bint Safwaan. The hadith of Talq ibn ‘Ali says that the Prophet (blessings and peace of Allah be upon him) was asked about a man who touches his penis whilst praying; is he required to do wudu? He said: “No; it is just a part of you.” And the hadith of Busrah says: “Whoever touches his penis, let him do wudu.”
And we say: If that is done with desire, then wudu becomes obligatory, but if it is without desire, then it is not required. This detail is indicated by the words of the Prophet (blessings and peace of Allah be upon him): “it is just a part of you.” So if he touches it like touching any other part of the body (then it does not invalidate wudu). It is well-known that a person would never touch any other part of his body with desire, is that not so? So we say: If you touch it like you touch any other part of your body, without desire, then you do not have to do wudu, but if you touch it with desire, then you have to do wudu, because perhaps something may come out of you in the event of desire, without you realising.
To sum up: touching the penis of an adult or a minor does not invalidate wudu unless it is accompanied by desire. The one who washes the private part of an infant definitely does not feel desire.
End quote from Liqa’ al-Baab al-Maftooh.
What is more likely to be correct, and Allah knows best, is the second view, which is that the mother’s wudu is not invalidated if she touches the ‘awrah of her infant, because this is something that happens a great deal, yet there is no report from the Prophet (blessings and peace of Allah be upon him) to indicate that he instructed the womenfolk of the Sahaabah to renew their wudu every time they needed to touch their children’s private parts, even though mothers often need to do so (when washing and bathing their children and so on).
And Allah knows best.