Ben Blakeley, the ex-boyfriend of the pregnant 17-year-old, strangled and buried her in his uncle's grave in Didcot, Oxfordshire, in December 2013.
He admitted affray in connection with an incident at Didcot Parkway station on 22 October 2013.
Blakeley, 23, from Reading, was given a concurrent eight month sentence at Oxford Crown Court.
He was jailed for life in July last year for the murder of Jayden.
Jayden was last seen alive on 3 December. Her body was discovered two weeks later on 18 December in a recently disturbed grave at All Saints' Church in Didcot.
Blakeley's brother Jake, 18, of Abbotts Road, Didcot, was jailed for three years for perverting the course of justice.
A man who is serving life for murdering teenager Jayden Parkinson has been given a further sentence for affray.