Does Gwaine know Merlin has magic?

Morgana in the TV series, Merlin, is said to be King Uther's ward, But really in the legend she is Arthur's evil step sister Morgan La Feye.

In the first series there is some suspision into whether Arthur and Morgana fancy/love each other and the same with Merlin! But soon after Arthur is in love with Guinevere which is in the Arturian Legend. So that leaves Merlin but soon after in late Season 3 and 4, She is evil and hates both of them.So, Morgana loves niether Arthur nor Merlin.