Contradiction with John 11:4
While Mark 5:35 relays the notion of death as final, John 11:4 emphasizes that sickness (and by extension, death) is ultimately for the glory of God, not to end in finality.
John 11:4: When Jesus heard [that], he said, This sickness is not unto death, but for the glory of God, that the Son of God might be glorified thereby.
Contradiction with Luke 8:50
Where Mark 5:35 indicates a sense of hopelessness with the girl's death, Luke 8:50 contradicts it by encouraging faith and asserting that she will be made whole.
Luke 8:50: But when Jesus heard [it], he answered him, saying, Fear not: believe only, and she shall be made whole.
Contradiction with Mark 5:39
In Mark 5:35, the child's death seems conclusive, but just a few verses later in Mark 5:39, Jesus contradicts this finality by stating the child is not dead, but sleeping.
Mark 5:39: And when he was come in, he saith unto them, Why make ye this ado, and weep? the damsel is not dead, but sleepeth.