Settlement deed with lifetime intereet

What property (ies) are involved in settlement deed in your favour qua "life interest" ?

Show the document to a local prudent lawyer for proper appreciation of facts and professional advise.

 Any person who is the sole owner of a self-acquired property can bequeath by way of will. 

If the settlement deed is absolute and if your mother is having the capacity to have that asset and has the rights to execute such settlement deed, you can execute the will.in your favour and get it registered.  Who is at present having possession and enjoyment and what was the date of settlement deed, whether settlement deed has stated any conditions are to be studied by a local advocate for proper guidance.

Yes, you may execute Will or even a gift deed benefitting your  wife and children. However, even otherwise, rights of your legal heirs cannot be disturbed or frustrated.