As a policy owner, your mother-in-law might have left the dividends to accumulate in the contract. Perhaps you could propose her withdrawing her dividends prior to assigning it over? If she still isn't interested, well then you really can't consider this policy as part of your life insurance program.
If you guys apply for new life insurance, you will be asked about all existing coverage. You could bring up the policy on your wife, but say you don't know anything about it. A good agent will ask if you can get a copy of the policy (which he should have for your needs analysis). This could at least get a copy of the policy in your hands.
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Espiritu - SWTOR (retired)
Espiritu (MajorMUD, UO, DAoC, SB, FFXI, WoW, WAR, Travian, SC2, SWTOR)