Kirstie,
Thanks for your help - much appreciated.
Just had a quick look and Martha is there along with Robert twice - once with Holdon as the mothers surname and once with Hotson. I've since found a burial for Robert Wicks, infant, at St John de Sepelchre church in 1826. i think both Roberts are to the same parents but the mothers surname was mistranscribed, as I have more information for Robert later in life. Really I need to get the information from scans of the parish records (or possibly bishops transcripts?) to double check if my theory is correct.
Bean