Husband passed away how can I claim my streedhan

My husband passed away last year in May'2015, at that time I was not aware for the right of streedhan a woman possess and my in laws took all the jewellery including managalsutra back from me...though I was not ready to give the same to them due to emotional connect with everything that's my husband's memory ..but they pressurized me and get everything from me, what should I do to get it back...??