A cut and sew "overlock" sewing machine for sewing at least two flaps (3a, 3b) of fabric, the flaps being superposed to one another and belonging to one or more textile articles, the machine comprising at least: - a needle plate for supporting at least two superposed flaps (3a, 3b) of fabric of one or more sliding textile articles for the formation of sewing stitches (10a, 10b, 10c), the needle plate being provided with through-openings defining respective seatings for passage of sewing needles and with at least a lateral appendage defining a running line for the sewing, said needle plate being provided with at least two of said seatings, each configured for being crossed by at least a respective sewing needle, said needle plate being further provided with respective separating portions suitable for at least partly separating each seating for passage of sewing needles from the adjacent seatings for passage of adjacent sewing needles, at least at the needle passage zone, for enabling formation in parallel of at least two stitches (10a, 10b, 10c) that are distinct and reciprocally distanced from one another, - a lower crochet provided with at least an eyelet and fed at least with a binding yarn; - an upper crochet; - an advancing device suitable for advancing said flaps (3a, 3b) of superposed fabric along an advancement direction with respect to said needle plate during a sewing operation; - a device for cutting said flaps (3a, 3b) of superposed fabric at a fabric cutting line, in proximity and upstream of said lateral appendage along said advancing direction of said flaps (3a,3b) of fabric; - at least a sewing yarn feeder for needles, able to supply sewing yarn to the needles of said sewing machine; - at least a binding yarn feeder, able to supply binding yarn to said lower crochet; - a recall device of the binding yarn from said lower crochet; - at least a sewing needle-holding device; - at least two sewing needles mounted on said needle-holding device, the needles being reciprocally flanked, aligned to one another and fed with respective sewing yarns, said sewing needles being able to pass through said seatings of said needle plate such as to sew said superposed flaps (3a, 3b) of fabric; characterised in that said lower crochet is provided with an additional gripping portion for said sewing yarn, suitable for interacting, in a lower position to said needle plate, with at least a sewing yarn destined to form at least a first sewing stitch of said sewing stitches (10a, 10b, 10c) such as to determine a predefined enlargement of said first sewing stitch under production on said sewing machine. - a needle plate for supporting at least two superposed flaps (3a, 3b) of fabric of one or more sliding textile articles for the formation of sewing stitches (10a, 10b, 10c), the needle plate being provided with through-openings defining respective seatings for passage of sewing needles and with at least a lateral appendage defining a running line for the sewing, said needle plate being provided with at least two of said seatings, each configured for being crossed by at least a respective sewing needle, said needle plate being further provided with respective separating portions suitable for at least partly separating each seating for passage of sewing needles from the adjacent seatings for passage of adjacent sewing needles, at least at the needle passage zone, for enabling formation in parallel of at least two stitches (10a, 10b, 10c) that are distinct and reciprocally distanced from one another, - a lower crochet provided with at least an eyelet and fed at least with a binding yarn; - an upper crochet; - an advancing device suitable for advancing said flaps (3a, 3b) of superposed fabric along an advancement direction with respect to said needle plate during a sewing operation; - a device for cutting said flaps (3a, 3b) of superposed fabric at a fabric cutting line, in proximity and upstream of said lateral appendage along said advancing direction of said flaps (3a,3b) of fabric; - at least a sewing yarn feeder for needles, able to supply sewing yarn to the needles of said sewing machine; - at least a binding yarn feeder, able to supply binding yarn to said lower crochet; - a recall device of the binding yarn from said lower crochet; - at least a sewing needle-holding device; - at least two sewing needles mounted on said needle-holding device, the needles being reciprocally flanked, aligned to one another and fed with respective sewing yarns, said sewing needles being able to pass through said seatings of said needle plate such as to sew said superposed flaps (3a, 3b) of fabric;