Family of Marokopa children missing with dad Tom Phillips for five months worry police aren't doing enough to find them

Thomas Phillips has been missing for five months with his three young children, Jayda, Ember and Maverick Phillips. Photo / File

A sibling of three Waikato children missing for the past five months says she worries police and other authorities are not taking the disappearance seriously.

Father Tom Phillips is suspected of taking the children - Jayda, 8, Maverick, 7, and Ember, 6, - into remote bushland near coastal town Marokopa in early December 2021.

He has only reportedly been seen once since then. The children have not been seen.

Their older half-sister says her worried family members feel the police have spent months dragging their feet without taking serious steps to find the children.

Police insist they are taking the disappearance "very seriously".

Their latest appeal for public help to find Phillips said officers had "growing concern" for the children's welfare.

But the children's adult sister questions "why is there growing concern now and not right at the beginning" when they went missing.

"It's been five months, it's ridiculous," she says.

The incident is the second within months in which Phillips has disappeared "off the grid" with his kids.

Police earlier launched a major search for him and his children in September last year when his ute was found on Kiritehere Beach with water lapping at its tyres, sparking fears the family could have been washed out to sea.

Emergency service teams and members of the local community and iwi spent 17 days looking for him before he and his children turned up at his parents' home on September 28.

Waikato West Area Commander Inspector Will Loughrin initially said Tom Phillips had not violated any court restrictions and done nothing wrong in that regard. Photo / Mike Scott

They had been staying in a tent in dense bush, his family said.

Police charged him with wasting police resources.

However, Phillips then went "off the grid" again in early December.

The young children's mother and older adult half-sisters posted on Facebook soon after calling for help finding the children, saying they wanted "these poor babies back".

When Phillips left in December, police said was he not violating any court orders.

"In terms of current court restrictions of what he can and can't do, he's doing nothing wrong," West Waikato police area commander Inspector Will Loughrin said.

Phillips later missed his January court appearance where he was due to face the charge of wasting police resources. Police subsequently issued a warrant for his arrest for failing to show.

Police this week stepped up efforts to find him by appealing on TV show Ten 7 Aotearoa on Thursday for public help tracking him down.

"Police staff focused on locating Phillips and the children continue to follow up information as it is received," police now say in a statement.

"This includes checking all possible locations of interest as they are identified."

People wait outside Te Kuiti District Court for Tom Phillips to appear at his first court hearing. Photo / Mike Scott

Police believe someone in the community is helping Phillips and urged that person to come forward and share information.

"Police, along with the children's mother, grandparents and extended family have growing concerns for their welfare especially as we head into winter," Loughrin said this month.

Police also say there are a number of "complexities and dynamics" involved in the situation.

But the children's oldest sister says the family has had to spearhead every new effort to bring attention to the missing children.

A map of the area in which Phillips' car was found when he first disappeared for 17 days in September last year. Image / File

She says recent media reports and the police Ten 7 Aotearoa TV show seemed to only take place after the family started a petition calling on police, Oranga Tamariki and Ministry of Education to do more.

"I can understand the hesitation to initiate a search party resembling that of September 2021, but I cannot justify it to myself," the sister says in her petition.

"We have gone from one extreme to another - a high profile search, reported on daily, to a multiple missing person's case that people are unaware of."

She says her family have no idea where the children are or how they are doing.

Are they receiving home-schooling, do they need medical care, are they getting fresh vegetables and eating well - no one knows because no one has any idea where they are, she says.

She says she was 12 when her mother - who is also the mother of the young children - married Phillips.

Since her half-sisters and brother were born, she has been a constant part of their life, travelling regularly from the South Island to see them.

"I've never gone more than a month without talking to the kids in their whole life," she says.

Youngest child Ember recently celebrated her sixth birthday while missing.

"We haven't been able to see the kids grow up and we've missed all those moments," their sister says.

"That is a lot of time he has taken from us ... and in a worst case scenario they never come back."