Be gentle - it's my first post.
Family rail ticket with Chiltern railways. 2 adults and 2 children to London Marylebone. Additional children for £1 each. just buy ticket at the station - all stations listed on website, but think it's from Kidderminster to Leamington Spa. Outbound journey must arrive in London after 10am weekdays and any time on weekends, return same day. Rail tickets can also be used for 2 for 1 on certain London attractions.