If Matthew had any siblings I can find no reference to them.
If St. Matthew had any siblings, there is no record of them.
no
If Lucy had any siblings there is no record of them.
If Valentine of Rome had any siblings there is no record of them.
If Monica had any siblings, there is no surviving record of them.
As far as we know, Matthew was never married nor did he father any children.
There is no mention in any biographies about any possible siblings of Patrick.
Historical records are unclear about Saint Cecilia's siblings. Some sources suggest she had brothers, while others do not mention any siblings. The focus is often on her life as a martyr and patron saint of musicians.
If Sophia had any siblings, there is no record of them.
If Barnabas had any siblings we have no record of them.
There is no definitive information about Saint Genevieve having any siblings. She is commonly believed to have been an only child.
If Matthew had any illnesses, there is no mention of them in scripture nor in tradition.