Judge Maryanne Trump Barry presides on the 4th federal circuit Court of Appeals, and certainly has all the traditional requirements for appointment to the SCOTUS, except perhaps one--she's 79 years old, which almost certainly precludes her from consideration. But it begs the question anyway, has a President ever nominated a sibling or a spouse to the federal courts? It would seem to me that such a move would violate the spirit of the separation of powers.
Well, all presidents have been men, until the 1980s all justices were men, and same sex marriage has only been available since the 1990s. So until the 1980s, no one could have nominated a spouse. No justices are openly in a same sex relationship, so we can put aside any male spouses being nominated.
There is only one female justice who is not currently on the court: Sandra Day O'Connor. Her husband was not a president. Bill Clinton and Barack Obama nominated all the current female justices, none of whom are their wives. Harriet Miers is the only female nominee who failed to be appointed, and she was not married to George W. Bush.
The analysis of siblings would be more complicated, as it would have been possible for any president to have appointed a sibling. However, no justice was nominated by a president with the same last name (either successfully or not). So probably not. Still barely possible if they had different last names for some reason.