So, there is legitimate doubt as to whether there really were two thieves. Either way, we can not say what their family background was.
Two thieves
The scriptures only give reference to two thieves who were crucifies along side Christ. This was done so that the answer to one of the thieves could be know by all. That of there being different degrees of glory in heaven to which all mankind will be asigned to one.
Crucufixion was a common form of execution. We do not know the specific charges against the criminals who were crucified with Jesus. There was nothig special about them; Jesus was crucified as a common criminal.
Jesus was crucified on a cross next to two thieves on a hill called, Golgatha.
There is nowhere in any translation of the bible where you will read about Jesus being hanged with thieves. However, you can read about Jesus being crucified with two robbers (thieves) in Matthew 27: 38.
Two thieves were crucified with him, one on his right and one on his left.
See Matthew 27: 38 - "Two robbers were crucified with him, one on his right and one on his left".
According to the Bible, Jesus died before the two thieves who were crucified with him. This is commonly referred to as the crucifixion of Jesus Christ.
For theological reasons, Jesus had to be crucified between two common thieves to show the actions of the Jews by disregarding Jesus' teachings deserved the anti-Jewish sentiment that lasted nearly 2000 years. Only those who committed high treason were crucified: thieves were not crucified. One of the blatantly historical mistakes in the gospels.
One possibility is : 2 Thieves Crucified with Jesus.
Dismas and Gestas were the thieves Mary and Joseph encountered on the way to Bethlahem. Dismas was also one of the thieves crucified with Jesus, the one who was forgiven by Jesus.
According the the Christian gospels, two other men were crucified with Jesus. These two men are variously described as thieves, criminals or rebels. Some fundamentalist Christians interpret the Gospels so that there were four men crucified with Jesus because of the different ways in which the men are described and because they take the Bible absolutely literally. So because one gospel says two "criminals" were crucified with Jesus and another says two "thieves" were crucified with Jesus there must have been four. Most people dismiss this and interpret the gospels more sensibly as there being only two other men crucified with Jesus.