Can the washing of the deceased be attended by one who does not need to be there?

Ibn Qudaamah (may Allah have mercy on him) said: It is makrooh for anyone other than the one who is washing the deceased and those who are helping him to attend the washing of the deceased, because it is makrooh to look at the deceased except if there is a reason, and it is mustahabb for those present to avert their gaze from him unless there is a reason to look at him. The reason for that is that there may be in the deceased a defect that he was concealing and that he would not like people to see or know about after his death, or there may be some issues that a living person would not like people to see or know about. And there may appear something that may indicate something objectionable and he may tell others about it, which is like exposing the deceased to scandal. And his ‘awrah may become uncovered and be seen. Hence we prefer for the one who washes the deceased to be trustworthy and righteous, so that he will conceal anything that he may see.

End quote from al-Mughni, 2/164 

An-Nawawi (may Allah have mercy on him) said: It is mustahabb to transfer him to a private place and conceal him from people’s gaze. There was no scholarly difference of opinion concerning this.

End quote from Sharh al-Muhadhdhab, 5/125 

There is no particular limit to the number of people who may be present; rather it is limited to what is needed. If there is an urgent need for more than one person, there is nothing wrong with that. This is indicated by the report narrated by Umm ‘Atiyyah (may Allah be pleased with her) who said: The Messenger of Allah (blessings and peace of Allah be upon him) entered upon us when his daughter died and said: Wash her three times or five times or more than that if you see fit, with water and lotus leaves, and put camphor or a little camphor in the last time. Then when you have finished call me.” Them when we had finished we called him… 

Narrated by al-Bukhaari. 1253; Muslim, 939 

But some of the scholars (may Allah have mercy on them) made an exception for the next of kin of the deceased and said that he may be present even if there is no need for him to be there, out of compassion towards the deceased. 

An-Nawawi (may Allah have mercy on him) said: Our companions said: it is mustahabb for no one to be present except the one who is washing him and whoever is needed to help him in washing. Our companions said: and the next of kin may enter, even if he does not wash him and does not help.

End quote from Sharh al-Muhadhdhab, 5/125 

al-Qaadi and Ibn ‘Aqeel among the Hanbalis said: And that is not unlikely. End quote from al-Insaaf, 2/486. 

Shaykh Muhammad al-Mukhtaar ash-Shanqeeti (may Allah preserve him) said: Some of the scholars granted a concession allowing some of the relatives (to be present) out of compassion, such as if it is his son and he wants to be present to wash him, and that may apply to some of the relatives so that it will help them to accept the decree of Allah, may He be glorified and exalted, because they may see signs that are indicative of good and that will help the relatives to be patient. And this is something well known; perhaps they will wash him and will see good signs whilst washing him, so that will help his relatives to be patient and seek reward with Allah for their loss.

End quote from Sharh az-Zaad. 

And Allah knows best.