Yes if the purpose is to mourn the loss of a loved one or friend, or to comfort and support the mourners because of a connection to the deceased or to the mourners. It is very commonplace -- and it is not limited to Christians -- people of all faiths who have those purposes are welcome. Is there a family that might take exception? Of course, but that would be true for any faith based on personal choice. For instance, sometimes a family will have a family or private funeral only; then nobody other than the specific invitees are welcome.
There is no issue with Jews attending Catholic funerals from the perspective of the Catholic Church. However, most Jews will not enter a church due to Jewish law prohibiting participating in religious services of another religion.
Yes, anyone, regardless of religion, is welcome at Jewish funerals.
This is not true. Children are permitted at funerals.
Non Trinitarian Christians, however those restriction were modified with the first Jewish settlement.
There are no Jewish Christians.
The majority of people who refer to themselves as "Jewish Christians" have zero Jewish heritage, they are mainly Christians.
Jewish funerals have several customs. After death, the body isn't to be left unattended. The deceased is buried in a simple wooden casket without any metal parts.
The first Christians were Jewish.
Christians believe that Jesus was the Jewish Messiah. Jews disagree.
To welcome the child into the Jewish community.
There is no issue with Jews attending Protestant funerals from the perspective of the Protestant Church. However, most Jews will not enter a church due to Jewish law prohibiting participating in religious services of another religion.
No.
They didn't.