No one really knows!
He christened his twins, Hamnet and Judith in 1585, and then disapppeared!
He surfaced 7 years later, in London, pilloried by a dissolute playwright Robert Greene, who introduced him with the tirade, "There is an upstart crow among us!"...
Shakespeare was ALREADY a well known playwright at this time, having first written the Henry VI series of three plays, shortly to be followed by Richard 111 to complete the Tetralogy, whilst in between filling in with Titus Andronicus, (written in Latin) and one or more comedies.