Karalina Garwood was in a relationship and living with Adam Taylor when he became involved with Ms Munnings and when she vanished in July 2008.

Ms Munnings and Mr Taylor had a baby together about two years before her disappearance, but Ms Garwood did not find out about it until the boy was six months old.

Ms Munnings was 16 when she became involved with Mr Taylor, who was in his 30s at the time.

Ms Garwood gave evidence to the inquest in Burnie yesterday about an abuse of trust by her former partner in relation to his relationship and communication with Ms Munnings on several occasions.

She said she found a secret phone that Mr Taylor used for Ms Munnings to contact him and later found a SIM card in one of his pockets while she was doing laundry.

On July 23, 2008, the last day Ms Munnings was seen, Mr Taylor went home agitated and stressed, Ms Garwood said.

He had turned up unexpectedly at the house about 2.45pm when he was supposed to be at work. Ms Garwood said he needed to swap cars to take a brick saw somewhere on his ute.

He left about 3.30pm and returned after 6pm.

When he came back inside, he told Ms Garwood that he thought someone had tried to steal the dinghy they had outside the house, because it was down at the water's edge on the beach when he got home.

Ms Garwood told the inquest she had been outside with one of her sons and he was playing in the dinghy about 5pm and it was still where it was supposed to be.

She did not see or hear anyone come to the side of the house after that.

Shortly after arriving home, Mr Taylor went down to retrieve the dinghy. It was dark and he was out there for about half an hour or 40 minutes before Ms Garwood called him to come back and say goodnight to the boys.

When he went back into the house, he was wet up to his crotch, the inquest heard.

Ms Garwood said he had a shower and got changed after that.

The inquest will resume on December 12, with Mr Taylor expected to give evidence that week.