Tina,
Your son will get married between 21/01/2018-19/02/2018 or if this period is missed then he will get married in 12/03/2018-06/05/2018.
Effects of mangal dosha are being reduced as Mars is exalted in the Navamsa but proper matching of horoscopes must be done for marital happiness.
God Bless,
Astrologer Akash.
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