Liverpool's six-year wait for a trophy was ended by a Gerrard but it was Cardiff's Anthony, cousin of Reds captain Steven, who had the decisive involvement.
The 26-year-old, on as a substitute in extra time, missed the penalty in a shoot-out which gave the Merseysiders' a record eighth League Cup.
It was cruel not only on the defender - who was consoled by his cousin at the end - but the rest of his team who had seen their early lead overtaken but remained resilient and found the strength to snatch an equaliser with two minutes of an absorbing final remaining.
Joe Mason had given the Bluebirds a first-half lead but goals from Martin Skrtel and, in extra time, Dirk Kuyt had put Kenny Dalglish's side within touching distance of the trophy before Ben Turner pegged them back.
So it went to spot-kicks, where Liverpool had lost only two in 12 previously, and although the early efforts were poor, Glen Johnson scored the fifth and Gerrard missed.
Their first visit to Wembley in 16 years was eventually worth the wait and the hope at Anfield, and among fans, will be that this cup will be the start of another era filled with silverware.
Over the last 40 years the Reds have won a trophy early in the decade and gone on to add to it.
In Dalglish they certainly have someone who knows plenty about accumulating cups of every kind and this victory put him alongside Sir Alex Ferguson and Jose Mourinho as the only managers to win all three major domestic competitions.
They also equalled Manchester United's record of 15 domestic cup wins.
Things looked like they would go to plan for Dalglish's side when the Cardiff crossbar was rattled inside two minutes.
Steven Gerrard raced 60 yards on a quick counter-attack but Johnson's shot which beat goalkeeper Tom Heaton and came back off the crossbar, with Gerrard blazing over the rebound, was the closest they came to threatening Cardiff's goal in the first half.
The Bluebirds created two better chances and, crucially, converted one.
Having snatched at a shot from Don Cowie's clever movement and backheel Kenny Miller did not make the same mistake twice.
The former Rangers front man was afforded all the time and space he required in the 19th minute when he picked up the ball just outside the area.
When Daniel Agger eventually closed him down Miller slid a pass into the space behind the centre-back where Mason collected and fired beyond Jose Reina.
The rest of the half saw Liverpool dominate but rarely trouble Cardiff.
Stewart Downing was their most creative outlet with a succession of crosses from the left but the Bluebirds dealt with them well enough, relying on Liverpool's over-complication and profligacy.
Charlie Adam flashed a low drive narrowly wide of Heaton's left-hand post while late in the half Andy Carroll was denied a clear close-range shooting opportunity when Cardiff captain Mark Hudson's outstretched leg hooked the ball away.
Liverpool fans tried to evoke memories of their second-half comeback in Istanbul in the 2005 Champions League final with a rendition of You'll Never Walk Alone at the break.
The situation was not quite as dire as that night but certainly Dalglish's side needed to find more composure and their clinical side.
Luis Suarez was starting to have more of an influence and drew the first real save from Heaton with an angled shot and was denied by Kevin McNaughton's perfectly-timed intervention just as he was about to unload from close range.
The appearance of former Cardiff striker and boyhood fan Craig Bellamy for the ineffectual Jordan Henderson brought, probably for the first time in cup final history, a standing ovation from both sets of fans.
Liverpool's salvation, however, was to come from an unexpected source.
Downing's 60th-minute corner was nodded on by Carroll to Suarez whose header came back off the post and Skrtel showed the composure in front of goal unbefitting a centre-back by taking a touch and slamming home the equaliser.
Turner had a chance to be Cardiff's hero with six minutes to go but planted his far-post header into the side-netting.
Miller should have won it for the Bluebirds in normal time when a quickly-taken free-kick caught the defence napping but the Scot, in acres of space in the penalty area, shot over with the goal at his mercy.
Barely a minute into extra time Andrew Taylor cleared Suarez's header from a Bellamy corner off the line before Anthony Gerrard finally got the chance to square-up against his more illustrious cousin when Hudson was forced off with cramp.
Three minutes into the second period of extra time Liverpool took the lead when Kuyt drilled home the rebound from his own cross.
The Dutchman then headed a shot off the line but got himself in a tangle at the resulting corner to allow Turner to force penalties.
In the shoot-out which followed Steven Gerrard and Adam missed for Liverpool, Miller, Rudy Gestede and Anthony Gerrard for Cardiff.