(Photo: Stanislas Brochier)

"And Belgium's number 27, Boon, finds the back of the net again!" As the commentator's voice rings out across the stadium, the Boon family can celebrate again as either Jill or Tom score yet another goal for their country. There have been siblings playing in national hockey teams before, and there are family connections all over this Hockey World Cup – for example, Wendy and Tony Stewart are umpire and judge respectively; Seve van Ass and Paul van Ass are father and son, player and coach – but very few names capture the imagination in quite the same way as the Boons.

For 24-year-old Tom and his elder sister, 27-year-old Jill, this Hockey World Cup is a chance to reinforce Belgium's reputation as a growing force on the global hockey stage. The men are currently ranked 5th, while the women are ranked 12th – having moved up the rankings from 27th place in just eight years – and while the men have aspirations to win a medal, for Jill and her teammates, it is all a learning process and the chance to compete against the very best in the world. Speaking at the recent Champions Challenge, where Belgium failed to live up to their billing as one of the pre-tournament favourites ( they finished sixth after losing a shoot-out to Korea), Jill Boon said: "We are a side that is hungry for success and we take each experience for what it is. If we lose, we learn from our mistakes and come out better next time. But this is a team that is desperate to win."

Certainly, the two opening games at this World Cup have provided very different experiences for the Boon siblings. While Tom was banging in the goals against Malaysia, just an hour later Jill was working hard to stop the Netherlands running riot. The final scoreline of 4-0 was disheartening, but with a difference in rankings of 12 places, to be expected. In their previous games, Tom's team had scored a last minute goal to secure a 3-2 win over India, while the women were on the wrong end of a 4-3 thriller against New Zealand. After the Netherlands match Jill said: "We knew that the game against Holland was going to be really hard, they are really sharp. But I was really happy for Tom scoring four goals. We are always like that, supportive of each other and sometimes critical of each other too."

The environment in which the Boon's grew up certainly played a part in their sporting achievements. Born into a hockey family – grandmother Jacqueline Ronsmans was a Belgian international player, as was their mother Carine Boon-Coudron, while uncle Marc Coudron played a record

358 games for Belgium – Jill says that most of their childhood was spent on a hockey pitch. "Even messing around on the side of the pitch Tom and I would have a small competition, like the nicest goal, the highest in the net. We don't do that now!"

She adds that while growing up, the whole family was involved in the logistics of getting from one game to another. "We learnt to manage it pretty well. We've been doing it since we're children, there were three hockey players in the family, my mother was playing and coaching my team and my father was coaching Tom on Saturday morning. We all trained at different times as well. The good thing now is that we often play at the same tournaments. But it's really important to have your family supporting you, they are our first critics after the game.

We really want to thank them because it's far from being easy!"

At this World Cup the Boon phenomena has been reinforced by Tom's opening goal-fest against Malaysia. Scoring four goals in one match during a World Cup has only been achieved by two other players, both from the Netherlands: Taco van den Honert in 1994, against Belgium and Taeke Taekema against India in 2006. When opposition coaches think about their tactics in matches against the Red Lions, the main question is 'How to stop Boon from scoring?"

The Boon siblings have very different goals at this World Cup, and while much of the talk is likely to centre around Tom's goal tally and the Red Lions medal prospects, Jill, who is approaching 200 caps for her country, can take pride in her role at the core of this developing Red Panthers revival. She will be delighted if the Red Panthers finish above their ranking place. But ultimately both Boons love winning and there is no doubt that if Tom were to stand on the podium on 15 June no-one would be prouder or cheering more loudly than his older sister.

Tom Boon